Mass balance model for calculation of ionic input loads in atmospheric fallout and discharge from a mountainous basin / Un modèle du bilan massique pour le calcul de la prise de charges ioniques dans les retombées atmosphériques et le débit

Open Access
Publisher Website
Google Scholar
Abstract
A mass balance model is designed to determine the contribution of ionic loads in atmospheric fallout to discharge from a pristine forested mountainous basin in British Columbia. Input to the model consisted of measurements of weekly precipitation amounts (mm) and ionic concentrations (mg 1−1) in bulk fallout on four elevation zones of an experimental basin. Output data consisted of instantaneous hydrometric measurements, expressed in flow units per basin area (mm) and ionic concentrations (mg 1−1) measured in weekly intervals at the basin outlet. The weekly data on volume weighted ionic concentrations in bulk fallout and discharge were used for calculation of monthly ionic loads (kg ha−1 month−1) and their monthly input-output balances. The annual loads (kg ha−1 year−1) in bulk fallout and discharge as well as the annual input-output balance were determined from the monthly loads. Implication of the hydrochemical balance for precipitation and stream chemistry variations, weathering, erosion and denudation rates in a perhumid mountainous basin in coastal British Columbia is discussed.